Improvement in air-pumps



B. T. BABBITT.

AIR-PUMP.

Nn.176,265. Patented Apri118, 1876.

N-PETERS, FNDTO-LITHOBRAPHEW, WASHINGTON. D C.

UNITE STATES PATENT ()FFIGE.

BENJAMIN T. BABBITT, OF NEW YORK, N. Y.

IMPROVEMENT IN AIR-PUMPS.

Specification forming part of Letters PatentNo. 176,265, dated April 18, 1876; application tiled J October 6, 1875.

To all whom it may concern Be it known that I, BENJAMIN T. BABBitr'r, D of New York, in the county and State of New York, have invented a new and useful Iniprovement ii'1,Aj1'-,-Pumps; and I do hereby declare that the following is a full, clear, and exact description of the same.

The object of my invention is to prevent the heating of the piston and rod of an air pump; and it consists in constructing the pis- 1011 and rod holl ow, and connecting it with a water chamber or reservoir by a pipe entering the piston-rod, whereby the heating is prevented by means of water circulating in the interior of the hollow piston and rod.

The accompanyingdrawing represents a sectional view of an apparatus constructed according to my inven tion.

The cylinder B is of any suitable construction, and provided with valves arranged and operating in any suitable manner. The pision D and piston-rod E are. made hollow, and attached together by any suitable means. The piston is attached to the rod about midway of its length, so that the ends of said rod work through the opposite ends of the cylinder. The end of the rod which is nearest to or connected with the driving-power is closed, and the opposite end is open and receives a water-supply pipe, by means of which water may be made to circulate in the interior of the piston and rod.

The water-supp] y pipe F may communicate with any suitable source of supply. It is here shown as connected with a. stationary reservoir, G, provided with an air-chamber, H, whereby provision is made for the displacement of the water on the forward stroke of the piston, and the replacement thereof on the backward stroke. The cylinder B is pro vided with stufling-boxes b b for the pistonrod, and the open end of the piston-rod is provided with a stufling-box, e, for the pipe F. The water chamber or reservoir may be large enough to hold a sufficient quantity of water to prevent the necessity of replenishing it, or it may be provided with inlet and outlet pipes, by means of which it may be kept constantiy supplied with cold water.

By this ora similar construction and arrangement of parts, a constant circulation of water is kept up in the interior of the hollow piston and piston-rod, and said parts are thereby prevented from becoming heated.

What I claim as new, and desire to secure by Letters Patent, is-

The combination of a hollow piston and piston-rod and a stationary water-supply pipe entering the piston-rod, substantially as and for the purpose herein described.

B. T. BABBITT.

Witnesses:

JOHN E. DOWLEY, FRED O. MEYER. 

